Merge pull request #1459 from bilawalsidhu/sameh/hud-google-lookups

Cut the Google requests the HUD summary makes on its own

changelog.d/1459-hud-place-lookups.md

@@ -0,0 +1,5 @@
+- Cut the Google requests the HUD's AI summary makes on its own. It no longer
+  looks up place names when no OpenAI key is configured, reverse-geocodes at
+  most two points instead of up to four, and looks up again only once the view
+  shows a different area, not after every small pan, so a small pan no longer
+  asks OpenAI for a new summary either (samehkhamis, #0000).

docs/CURRENT-STATE.md

@@ -4,6 +4,24 @@ Docker Compose mounts the checkout with the shared SELinux `:z` label so
 containers can read it on enforcing SELinux hosts. The separate image-owned
 `node_modules` volume and loopback-only port publishing remain unchanged.
 
+The HUD's AI summary line looks up place names for the view only when the
+summary can use them. The page asks `GET /api/openai/hud-summary/status` once;
+a server without an OpenAI key answers `{ configured: false }`, and the HUD then
+makes no reverse-geocode or Nearby Places request until the page reloads. A
+server without the route is asked once, and an unconfigured summary reply
+stops the lookups the same way. Each lookup reverse-geocodes at most two
+points: the view center alone below 10 km, the center and one viewport point
+up to 750 km, and two viewport points up to 3000 km; Nearby Places is still
+added below 25 km. A lookup is reused until the view center moves a quarter of
+the visible width, the camera's distance to the center doubles or halves, or
+the camera crosses one of those heights. The width is measured from the
+camera's distance to the view center, so terrain and tilt scale it. A reused
+lookup asks again only for what it did not get (a timeout, a failure, an empty
+answer); everything else is a cache hit. A small pan over a reused lookup
+repaints the last AI reply instead of asking for a new one. A host passing
+`cachedOnly` keeps reading every cached sample. Voice context lookups are
+unchanged.
+
 The HUD's LAT/LON degrees-minutes-seconds readout rounds the coordinate once, to
 hundredths of a second, and then splits it. A value within 0.005" of the next
 whole minute carries into the minutes and degrees, so `-122.35` reads

scripts/format-scope.json

@@ -1102,6 +1102,8 @@
   "src/cameraGlobeRotation.test.mjs",
   "src/voice/globeResetConfirmation.test.mjs",
   "src/hudDms.test.mjs",
+  "src/hudSummaryGate.test.mjs",
+  "src/voice/hudPlaceLabels.test.mjs",
   "src/voice/panel/preferences.test.mjs",
   "src/voice/panel/host.test.mjs",
   "src/voice/panel/manualPanel.test.mjs",

scripts/package-boundaries.json

@@ -1953,6 +1953,7 @@
       "src/hud.js",
       "src/hudLocality.js",
       "src/hudLocalityFormat.js",
+      "src/hudPlaceLookup.js",
       "src/hudSummaryResponse.js",
       "src/keySetup.js",
       "src/keySetupCore.mjs",

server/providers/openai/hud-summary.js

@@ -29,6 +29,19 @@ function toFiveWordHudSummary(value) {
 }
 
 async function handleHudSummary(req, res) {
+  // Capability probe: lets the HUD skip its paid place lookups when there is
+  // no summary to feed them to.
+  if (req.method === 'GET' && req.url?.split('?')[0] === '/status') {
+    res.statusCode = 200;
+    res.setHeader('Content-Type', 'application/json; charset=utf-8');
+    res.setHeader('Cache-Control', 'no-store');
+    res.end(
+      JSON.stringify({
+        configured: !keylessHudSummaryResponse(process.env.OPENAI_API_KEY),
+      }),
+    );
+    return;
+  }
   if (req.method !== 'POST') {
     res.statusCode = 405;
     res.setHeader('Content-Type', 'application/json');

src/hud.js

@@ -203,7 +203,13 @@ export class IntelHUD {
     this._dataManagerUnsubscribe = null;
     this._summaryDirty = true;
     this._summaryRequest = null;
+    this._summaryUnconfigured = false;
+    // The last place lookup and the view it answered for (see
+    // getBasemapLabelContext), reused until the view changes enough.
+    this._placeLabels = null;
     this._lastSummarySignature = '';
+    /** The reply painted for `_lastSummarySignature`, when it was accepted. */
+    this._lastSummaryText = null;
     this._summaryRevision = 0;
     // One-shot guards so the very first summary lands immediately instead of
     // waiting for the 15s interval tick: B) swap the "Awaiting telemetry..."
@@ -829,6 +835,15 @@ export class IntelHUD {
     if (this.summaryPolicy.canRequest?.() === false) return;
 
     const revision = this._summaryRevision;
+    // The place lookups below are paid Google requests made only to feed the
+    // AI summary, so a server without one must not be asked to make them.
+    if (!(await this._summaryAvailable())) {
+      if (revision !== this._summaryRevision) return;
+      this._summaryDirty = false;
+      this._setSummaryText(fallbackText, animate);
+      return;
+    }
+    if (revision !== this._summaryRevision) return;
     // Every caller invokes this as `void this._updateSummary(...)`, so nothing
     // owns the returned promise — a rejection escaping from here lands as an
     // unhandled rejection in the console. Building the context walks the live
@@ -851,6 +866,9 @@ export class IntelHUD {
     const signature = JSON.stringify(context);
     if (!force && signature === this._lastSummarySignature) {
       this._summaryDirty = false;
+      // A settle painted the fallback line over the reply this context
+      // already has; reused place labels make that common, so restore it.
+      if (this._lastSummaryText) this._setSummaryText(this._lastSummaryText);
       return;
     }
     if (this._summaryRequest) return;
@@ -858,6 +876,7 @@ export class IntelHUD {
     if (force) this._setSummaryText(fallbackText, false);
     this._summaryDirty = false;
     this._lastSummarySignature = signature;
+    this._lastSummaryText = null;
     const controller = new AbortController();
     let timedOut = false;
     const timeout = window.setTimeout(() => {
@@ -873,18 +892,16 @@ export class IntelHUD {
       const data = response.data;
       if (revision !== this._summaryRevision) return;
       if (isHudSummaryUnconfigured(response.status, data)) {
+        this._summaryUnconfigured = true;
         this._setSummaryText(fallbackText, animate);
         return;
       }
       if (!response.ok || !data?.summary) {
         throw new Error(data?.error || `HTTP ${response.status}`);
       }
-      this._setSummaryText(
-        hudSummaryMatchesProvenance(data.summary, context.feedProvenance)
-          ? data.summary
-          : fallbackText,
-        animate,
-      );
+      if (hudSummaryMatchesProvenance(data.summary, context.feedProvenance))
+        this._lastSummaryText = data.summary;
+      this._setSummaryText(this._lastSummaryText || fallbackText, animate);
     } catch (error) {
       // The 5 s timeout is a failure like any other; a move's abort (or
       // destroy's) is not.
@@ -918,12 +935,31 @@ export class IntelHUD {
     if (el) el.textContent = text;
   }
 
+  /**
+   * False once the summary service reports no AI summary: by its capability
+   * probe, when it has one, or by a deliberate unconfigured reply. Unknown
+   * stays available, as before.
+   */
+  async _summaryAvailable() {
+    if (this._summaryUnconfigured) return false;
+    try {
+      if ((await this.summaryService?.configured?.()) === false)
+        this._summaryUnconfigured = true;
+    } catch {
+      /* an unanswered probe leaves the summary as it was */
+    }
+    return !this._summaryUnconfigured;
+  }
+
   async _summaryContext() {
-    const labels = await getBasemapLabelContext(
-      this.viewer,
-      this.placeSearch,
-      this.basemapContext,
-    );
+    const revision = this._summaryRevision;
+    const labels = await getBasemapLabelContext(this.viewer, this.placeSearch, {
+      ...this.basemapContext,
+      previous: this._placeLabels,
+    });
+    // A slower build for a view the camera has left must not replace the
+    // newer view's lookup.
+    if (revision === this._summaryRevision) this._placeLabels = labels;
     const enabledLayers =
       this._dataManager
         ?.getAll?.()

src/hudPlaceLookup.js

@@ -0,0 +1,80 @@
+import { greatCircleMeters } from './geoDistance.js';
+
+/**
+ * When the HUD's passive place lookup may spend another reverse geocode or
+ * Nearby Places request. Every request is a paid Google call, and the HUD
+ * asks on its own whenever the camera settles, so a new view only earns a
+ * new lookup once it shows a meaningfully different area: the center has
+ * moved by a quarter of the visible width, or the camera's distance to the
+ * center has doubled or halved. The width is measured at the view center
+ * from that distance, so terrain under the camera and a tilted view scale it
+ * as they scale what is on screen.
+ */
+const MOVE_FRACTION = 0.25;
+const RANGE_RATIO = 2;
+/** Street-level views still need a small move before they count as new. */
+const MIN_SPAN_M = 100;
+const DEFAULT_FOV_RAD = Math.PI / 3;
+
+/**
+ * Describe the view a lookup answers for.
+ * @param {{latitude: number, longitude: number, rangeM: number, fovRad?: number, aspectRatio?: number, tier?: string}} view
+ *   `rangeM` is the camera's distance to the view center. `fovRad` and
+ *   `aspectRatio` are the Cesium perspective frustum's. `tier` names which
+ *   lookups the camera height calls for; a view in another tier is new.
+ * @returns {{latitude: number, longitude: number, rangeM: number, spanM: number, tier: string}}
+ */
+export function placeLookupView({
+  latitude,
+  longitude,
+  rangeM,
+  fovRad,
+  aspectRatio,
+  tier = '',
+}) {
+  const fov =
+    Number.isFinite(fovRad) && fovRad > 0 && fovRad < Math.PI
+      ? fovRad
+      : DEFAULT_FOV_RAD;
+  // Cesium's fov spans the wider screen dimension, so a portrait screen's
+  // width is narrower than it.
+  const aspect = Number(aspectRatio);
+  const horizontalFov =
+    Number.isFinite(aspect) && aspect > 0 && aspect < 1
+      ? 2 * Math.atan(Math.tan(fov / 2) * aspect)
+      : fov;
+  const range = Math.max(1, Number(rangeM) || 0);
+  return {
+    latitude,
+    longitude,
+    rangeM: range,
+    spanM: Math.max(MIN_SPAN_M, 2 * range * Math.tan(horizontalFov / 2)),
+    tier,
+  };
+}
+
+/**
+ * Whether `next` shows enough new ground to look its places up again.
+ * A missing or unusable previous view always does.
+ */
+export function placeLookupViewChanged(previous, next) {
+  if (!previous || !next || previous.tier !== next.tier) return true;
+  const ratio =
+    Math.max(previous.rangeM, next.rangeM) /
+    Math.min(previous.rangeM, next.rangeM);
+  if (!Number.isFinite(ratio) || ratio >= RANGE_RATIO) return true;
+  const moved = greatCircleMeters(
+    { lat: previous.latitude, lon: previous.longitude },
+    { lat: next.latitude, lon: next.longitude },
+  );
+  return !(moved < MOVE_FRACTION * previous.spanM);
+}
+
+/**
+ * The viewport samples the HUD geocodes besides the view center: one more
+ * point. Sample 0 is the screen center, so it stands in for the center only
+ * when the center itself is not geocoded at this height.
+ */
+export function hudViewportSamples(samples, centerGeocoded) {
+  return centerGeocoded ? samples.slice(1, 2) : samples.slice(0, 2);
+}

src/hudSummaryGate.test.mjs

@@ -0,0 +1,187 @@
+// The HUD's place lookups are paid Google requests made only to feed the AI
+// summary, so a server without one must not be asked to make them.
+//
+// hud.js imports `mgrs`, which Node's ESM loader cannot read named exports
+// from, so a module hook swaps it for a stub before the import (the same
+// setup as hudPageVisibility.test.mjs).
+import { test } from 'node:test';
+import assert from 'node:assert/strict';
+import { registerHooks } from 'node:module';
+
+const MGRS_STUB_URL = 'gev-test-stub:mgrs';
+registerHooks({
+  resolve(specifier, context, next) {
+    if (specifier === 'mgrs') return { url: MGRS_STUB_URL, shortCircuit: true };
+    return next(specifier, context);
+  },
+  load(url, context, next) {
+    if (url === MGRS_STUB_URL) {
+      return {
+        format: 'module',
+        shortCircuit: true,
+        source:
+          'export function forward() { return "10SEG55776339"; }\nexport default { forward };\n',
+      };
+    }
+    return next(url, context);
+  },
+});
+
+const { IntelHUD } = await import('./hud.js');
+
+function installPage() {
+  const elements = new Map(
+    [
+      'hud-alt',
+      'hud-summary',
+      'hud-mgrs',
+      'hud-latlon',
+      'hud-bottom-line',
+      'hud-gsd',
+      'hud-coll',
+      'hud-ona',
+      'hud-mode',
+    ].map((id) => [id, { textContent: '' }]),
+  );
+  const previous = { document: globalThis.document, window: globalThis.window };
+  globalThis.document = {
+    hidden: false,
+    visibilityState: 'visible',
+    getElementById: (id) => elements.get(id) ?? null,
+    querySelectorAll: () => [],
+    addEventListener() {},
+    removeEventListener() {},
+  };
+  globalThis.window ??= {
+    setTimeout,
+    clearTimeout,
+    setInterval,
+    clearInterval,
+  };
+  const viewer = {
+    camera: {
+      pitch: -Math.PI / 2,
+      positionCartographic: { latitude: 0.53, longitude: -1.7, height: 600 },
+      computeViewRectangle: () => undefined,
+      moveStart: { addEventListener() {}, removeEventListener() {} },
+      moveEnd: { addEventListener() {}, removeEventListener() {} },
+    },
+  };
+  return {
+    viewer,
+    restore() {
+      for (const [key, value] of Object.entries(previous)) {
+        if (value === undefined) delete globalThis[key];
+        else globalThis[key] = value;
+      }
+    },
+  };
+}
+
+/** A HUD whose place lookup and summary service only count their calls. */
+function createHud(t, summaryService) {
+  t.mock.timers.enable({ apis: ['setInterval'] });
+  const page = installPage();
+  const hud = new IntelHUD(page.viewer, { summaryService });
+  t.after(() => {
+    hud.destroy();
+    page.restore();
+  });
+  const calls = { context: 0 };
+  hud._latestMetrics = { altM: 600 };
+  hud._summaryContext = async () => {
+    calls.context += 1;
+    return { placeLabels: ['Austin'], streetLabels: [], nearbyPlaceLabels: [] };
+  };
+  return { hud, calls };
+}
+
+test('a server that reports no AI summary gets no place lookups', async (t) => {
+  const service = {
+    calls: 0,
+    configured: async () => false,
+    async summarize() {
+      this.calls += 1;
+      return { ok: true, status: 200, data: { summary: 'never' } };
+    },
+  };
+  const { hud, calls } = createHud(t, service);
+  await hud._updateSummary(false, true);
+  hud._markSummaryDirty();
+  await hud._updateSummary(false);
+  assert.equal(calls.context, 0);
+  assert.equal(service.calls, 0);
+});
+
+test('an unconfigured reply stops the lookups for the rest of the page', async (t) => {
+  const service = {
+    calls: 0,
+    async summarize() {
+      this.calls += 1;
+      return {
+        ok: true,
+        status: 200,
+        data: {
+          configured: false,
+          code: 'OPENAI_NOT_CONFIGURED',
+          error: null,
+          summary: null,
+        },
+      };
+    },
+  };
+  const { hud, calls } = createHud(t, service);
+  await hud._updateSummary(false, true);
+  assert.equal(calls.context, 1, 'a server without the probe is asked once');
+  hud._markSummaryDirty();
+  await hud._updateSummary(false, true);
+  assert.equal(calls.context, 1);
+  assert.equal(service.calls, 1);
+});
+
+test('a configured or unknown summary keeps looking places up', async (t) => {
+  for (const configured of [true, null, undefined]) {
+    await t.test(String(configured), async (st) => {
+      const service = {
+        configured:
+          configured === undefined ? undefined : async () => configured,
+        summarize: async () => ({
+          ok: true,
+          status: 200,
+          data: { summary: 'Austin capitol district live' },
+        }),
+      };
+      const { hud, calls } = createHud(st, service);
+      await hud._updateSummary(false, true);
+      assert.equal(calls.context, 1);
+    });
+  }
+});
+
+test('an unchanged context restores its accepted reply over the fallback line', async (t) => {
+  const service = {
+    calls: 0,
+    configured: async () => true,
+    async summarize() {
+      this.calls += 1;
+      return {
+        ok: true,
+        status: 200,
+        data: { summary: 'Austin capitol district live' },
+      };
+    },
+  };
+  const { hud } = createHud(t, service);
+  const shown = () =>
+    globalThis.document.getElementById('hud-summary').textContent;
+  await hud._updateSummary(false, true);
+  assert.equal(shown(), 'Austin capitol district live');
+
+  // A small pan settles: the fallback line is painted and the reused labels
+  // give the same context, so no new request is made.
+  hud._setSummaryText('fallback line', false);
+  hud._markSummaryDirty();
+  await hud._updateSummary(false);
+  assert.equal(service.calls, 1);
+  assert.equal(shown(), 'Austin capitol district live');
+});

src/services/requests.js

@@ -71,6 +71,7 @@ export function createApplicationRequestServices({
   // Discovery is bounded; failed, malformed or timed-out probes are forgotten and not
   // retried for a short backoff, during which queries go to the server as
   // they would against an older server without the probe.
+  let summaryCapability = null;
   let boundaryCapability = null;
   let boundaryProbeRetryAt = 0;
   function boundariesConfigured() {
@@ -175,6 +176,23 @@ export function createApplicationRequestServices({
       },
     },
     summary: {
+      // The capability probe, asked once per page: true or false from a
+      // server that answers it, null (unknown) from one that does not.
+      configured() {
+        summaryCapability ??= request(`${urls.summary}/status`, {
+          signal: AbortSignal.timeout(3000),
+        }).then(
+          (response) =>
+            response.ok && typeof response.data?.configured === 'boolean'
+              ? response.data.configured
+              : null,
+          (error) => {
+            if (lifetime?.aborted) throw error;
+            return null;
+          },
+        );
+        return summaryCapability;
+      },
       async summarize(context, { signal } = {}) {
         return request(urls.summary, {
           method: 'POST',

src/services/requests.test.mjs

@@ -94,3 +94,24 @@ test('a failed probe is retried after its backoff, not on every query', async ()
     'GET /api/overpass/status',
   ]);
 });
+
+test('the summary capability probe is asked once and unknown when unanswered', async () => {
+  for (const [answer, expected] of [
+    [() => Response.json({ configured: false }), false],
+    [() => Response.json({ configured: true }), true],
+    [() => new Response('missing', { status: 404 }), null],
+    [() => Response.json({ configured: 'yes' }), null],
+    [() => { throw new TypeError('offline'); }, null],
+  ]) {
+    const seen = [];
+    const services = createApplicationRequestServices({
+      fetchImpl: async (url, init) => {
+        seen.push(`${init.method || 'GET'} ${url}`);
+        return answer();
+      },
+    });
+    assert.equal(await services.summary.configured(), expected);
+    assert.equal(await services.summary.configured(), expected);
+    assert.deepEqual(seen, ['GET /api/openai/hud-summary/status']);
+  }
+});

src/tooling/localServices.test.mjs

@@ -729,6 +729,29 @@ test('Realtime service configuration selects compatible endpoint/model without f
   assert.doesNotMatch(response.body, /server-fixture|voice\.example/);
 });
 
+test('the HUD summary status says whether a summary is configured, without calling OpenAI', async (t) => {
+  t.mock.method(globalThis, 'fetch', async () => {
+    throw new Error('the status probe must not reach OpenAI');
+  });
+  const handler = install(openAiRealtimeProxy()).get('/api/openai/hud-summary');
+  for (const [key, configured] of [
+    [undefined, false],
+    ['   ', false],
+    ['fixture-key', true],
+  ]) {
+    env(t, 'OPENAI_API_KEY', key);
+    const response = await request(handler, { url: '/status' });
+    assert.equal(response.status, 200);
+    assert.deepEqual(response.json(), { configured });
+    assert.equal(response.headers['cache-control'], 'no-store');
+  }
+  assert.equal(
+    (await request(handler, { url: '/' })).status,
+    405,
+    'only the status path answers GET',
+  );
+});
+
 test('OpenAI routes answer generically when the upstream or the request fails', async (t) => {
   env(t, 'OPENAI_API_KEY', 'fixture-upstream-secret');
   env(t, 'GEV_RATELIMIT_OPENAI_PER_MIN', undefined);

src/voice/gevActions.js

@@ -12,6 +12,11 @@ import { msg } from '../i18n/index.js';
 import * as Cesium from 'cesium';
 import { CITY_POIS } from '../cityPois.js';
 import { greatCircleKm } from '../geoDistance.js';
+import {
+  hudViewportSamples,
+  placeLookupView,
+  placeLookupViewChanged,
+} from '../hudPlaceLookup.js';
 import {
   findPoiByName,
   flyToGlobeView,
@@ -2692,13 +2697,20 @@ function runManagedVoiceNavigation(
   };
 }
 
+/**
+ * Place labels for the HUD's passive summary. It geocodes the view center
+ * and one more point. While the view still shows about the same area (see
+ * hudPlaceLookup.js) it answers for the points the last lookup asked about
+ * instead, so a settled camera does not buy a new set of Google requests for
+ * every small pan; those points are cache hits, and only what the last
+ * lookup did not get (a timeout, a failure, an empty answer) is asked again.
+ * `cachedOnly` reads the shared caches and makes no request.
+ */
 export async function getBasemapLabelContext(
   viewer,
   service = defaultGeospatial,
-  { cachedOnly = false } = {},
+  { cachedOnly = false, previous = null } = {},
 ) {
-  const { reverseGeocodeCache, nearbyPlacesCache } = cachesFor(service);
-  const samples = sampleViewportCartographics(viewer);
   const cameraHeightM = viewer.camera.positionCartographic.height;
   const target = getViewTargetCartographic(viewer);
   if (!target) {
@@ -2706,11 +2718,77 @@ export async function getBasemapLabelContext(
       placeLabels: [],
       streetLabels: [],
       nearbyPlaceLabels: [],
+      view: null,
+      lookup: null,
     };
   }
 
   const latitude = Number(Cesium.Math.toDegrees(target.latitude).toFixed(6));
   const longitude = Number(Cesium.Math.toDegrees(target.longitude).toFixed(6));
+  const view = placeLookupView({
+    latitude,
+    longitude,
+    rangeM: viewTargetRangeM(viewer, target, cameraHeightM),
+    fovRad: viewer.camera.frustum?.fov,
+    aspectRatio: viewer.camera.frustum?.aspectRatio,
+    tier: basemapLookupTier(cameraHeightM),
+  });
+  if (
+    !cachedOnly &&
+    previous?.lookup &&
+    !placeLookupViewChanged(previous.view, view)
+  ) {
+    // The same points again: what the last lookup got is a cache hit, and
+    // only what it did not (a timeout, a failure, an empty answer) is asked.
+    const labels = await basemapLabelsAt(previous.lookup, service, {
+      cachedOnly: false,
+    });
+    return { ...labels, view: previous.view, lookup: previous.lookup };
+  }
+  const samples = sampleViewportCartographics(viewer);
+  const lookup = {
+    latitude,
+    longitude,
+    cameraHeightM,
+    // Cache reads are free, so a cached-only host keeps every sample.
+    samples: cachedOnly
+      ? samples
+      : hudViewportSamples(samples, shouldReverseGeocode(cameraHeightM)),
+  };
+  return {
+    ...(await basemapLabelsAt(lookup, service, { cachedOnly })),
+    view,
+    lookup,
+  };
+}
+
+/** Which of the height-gated lookups a camera height calls for. */
+function basemapLookupTier(cameraHeightM) {
+  return [
+    shouldReverseGeocode(cameraHeightM),
+    shouldReverseGeocodeViewport(cameraHeightM) && cameraHeightM > 10000,
+    shouldFetchNearbyPlaces(cameraHeightM) &&
+      nearbyPlacesRadiusM(cameraHeightM),
+  ].join(':');
+}
+
+/** Camera distance to the view target, or the camera height without one. */
+function viewTargetRangeM(viewer, target, cameraHeightM) {
+  const position = viewer.camera.positionWC;
+  if (!position) return cameraHeightM;
+  const range = Cesium.Cartesian3.distance(
+    position,
+    Cesium.Cartographic.toCartesian(target),
+  );
+  return Number.isFinite(range) ? range : cameraHeightM;
+}
+
+async function basemapLabelsAt(
+  { latitude, longitude, cameraHeightM, samples },
+  service,
+  { cachedOnly },
+) {
+  const { reverseGeocodeCache, nearbyPlacesCache } = cachesFor(service);
   const cachedViewportPlaces = viewportPlacesFromCache(
     samples,
     cameraHeightM,
@@ -2748,7 +2826,6 @@ export async function getBasemapLabelContext(
     resolveWithin(placePromise, BASEMAP_CONTEXT_WAIT_MS, null),
     resolveWithin(nearbyPromise, BASEMAP_CONTEXT_WAIT_MS, []),
   ]);
-
   return {
     placeLabels: uniqueStrings([
       place?.formattedAddress,

src/voice/hudPlaceLabels.test.mjs

@@ -0,0 +1,359 @@
+// The HUD's passive place lookup spends paid Google requests on its own, so
+// it must look up the view center and one more point, and only again once the
+// view shows a different area.
+import { test } from 'node:test';
+import assert from 'node:assert/strict';
+import * as Cesium from 'cesium';
+import { getBasemapLabelContext } from './gevActions.js';
+import {
+  hudViewportSamples,
+  placeLookupView,
+  placeLookupViewChanged,
+} from '../hudPlaceLookup.js';
+
+globalThis.window = globalThis.window || { setTimeout, clearTimeout };
+
+/**
+ * A looking-down camera `heightM` above the ellipsoid. Ellipsoid picks map
+ * screen pixels linearly to degrees; the view target sits on terrain
+ * `groundM` high under the camera.
+ */
+function createViewer({ latitude, longitude, heightM, groundM = 0 }) {
+  const state = { latitude, longitude, heightM, groundM };
+  const canvas = { clientWidth: 1200, clientHeight: 800 };
+  const degreesPerPixel = () => state.heightM / 111_000 / canvas.clientHeight;
+  const camera = {
+    heading: 0,
+    pitch: -Math.PI / 2,
+    frustum: { fov: Math.PI / 3, aspectRatio: 1.5 },
+    pickEllipsoid(point) {
+      return Cesium.Cartesian3.fromDegrees(
+        state.longitude +
+          (point.x - canvas.clientWidth / 2) * degreesPerPixel(),
+        state.latitude -
+          (point.y - canvas.clientHeight / 2) * degreesPerPixel(),
+      );
+    },
+  };
+  Object.defineProperties(camera, {
+    positionCartographic: {
+      get: () =>
+        Cesium.Cartographic.fromDegrees(
+          state.longitude,
+          state.latitude,
+          state.heightM,
+        ),
+    },
+    positionWC: {
+      get: () =>
+        Cesium.Cartesian3.fromDegrees(
+          state.longitude,
+          state.latitude,
+          state.heightM,
+        ),
+    },
+  });
+  const scene = {
+    canvas,
+    pickPositionSupported: true,
+    pickPosition: () =>
+      Cesium.Cartesian3.fromDegrees(
+        state.longitude,
+        state.latitude,
+        state.groundM,
+      ),
+  };
+  return { viewer: { camera, scene }, state, degreesPerPixel };
+}
+
+/** Answers every lookup with a label naming the point it was asked about. */
+function createService() {
+  const calls = { reverse: 0, nearby: 0 };
+  return {
+    calls,
+    async reverseGeocode(latitude, longitude) {
+      calls.reverse += 1;
+      const point = `${latitude.toFixed(4)},${longitude.toFixed(4)}`;
+      return { formattedAddress: `Place ${point}`, labels: [`Area ${point}`] };
+    },
+    async nearby() {
+      calls.nearby += 1;
+      return [{ name: `Nearby ${calls.nearby}` }];
+    },
+  };
+}
+
+test('a view counts as new after a quarter-width move or a doubled distance', () => {
+  const view = placeLookupView({ latitude: 30, longitude: -97, rangeM: 1000 });
+  // A 60° field of view at 1 km shows about 1155 m across.
+  assert.ok(Math.abs(view.spanM - 1154.7) < 1);
+  const near = placeLookupView({
+    latitude: 30.002,
+    longitude: -97,
+    rangeM: 1100,
+  });
+  assert.equal(
+    placeLookupViewChanged(view, near),
+    false,
+    '~220 m is under a quarter width',
+  );
+  const far = placeLookupView({
+    latitude: 30.003,
+    longitude: -97,
+    rangeM: 1000,
+  });
+  assert.equal(
+    placeLookupViewChanged(view, far),
+    true,
+    '~330 m is over a quarter width',
+  );
+  const closer = placeLookupView({ latitude: 30, longitude: -97, rangeM: 500 });
+  assert.equal(placeLookupViewChanged(view, closer), true);
+  const farther = placeLookupView({
+    latitude: 30,
+    longitude: -97,
+    rangeM: 2000,
+  });
+  assert.equal(placeLookupViewChanged(view, farther), true);
+  assert.equal(placeLookupViewChanged(null, view), true);
+  // The antimeridian is a short hop, not a world away.
+  const west = placeLookupView({
+    latitude: 0,
+    longitude: 179.9999,
+    rangeM: 1000,
+  });
+  const east = placeLookupView({
+    latitude: 0,
+    longitude: -179.9999,
+    rangeM: 1000,
+  });
+  assert.equal(placeLookupViewChanged(west, east), false);
+});
+
+test('a portrait screen measures its narrower width', () => {
+  const landscape = placeLookupView({
+    latitude: 0,
+    longitude: 0,
+    rangeM: 1000,
+    aspectRatio: 1.5,
+  });
+  const portrait = placeLookupView({
+    latitude: 0,
+    longitude: 0,
+    rangeM: 1000,
+    aspectRatio: 0.5,
+  });
+  assert.ok(Math.abs(landscape.spanM - 1154.7) < 1);
+  assert.ok(Math.abs(portrait.spanM - 577.4) < 1);
+});
+
+test('a view in another height tier is new however close it is', () => {
+  const a = placeLookupView({
+    latitude: 0,
+    longitude: 0,
+    rangeM: 1000,
+    tier: 'x',
+  });
+  const b = placeLookupView({
+    latitude: 0,
+    longitude: 0,
+    rangeM: 1000,
+    tier: 'y',
+  });
+  assert.equal(placeLookupViewChanged(a, b), true);
+});
+
+test('the HUD geocodes one viewport point besides the center', () => {
+  const samples = [{ i: 0 }, { i: 1 }, { i: 2 }];
+  assert.deepEqual(hudViewportSamples(samples, true), [{ i: 1 }]);
+  assert.deepEqual(hudViewportSamples(samples, false), [{ i: 0 }, { i: 1 }]);
+  assert.deepEqual(hudViewportSamples([], true), []);
+});
+
+test('a regional view spends two reverse geocodes and a nearby search', async () => {
+  const { viewer } = createViewer({
+    latitude: 30.26,
+    longitude: -97.74,
+    heightM: 20_000,
+  });
+  const service = createService();
+  const labels = await getBasemapLabelContext(viewer, service);
+  // Before: the center plus three viewport samples (the first of them the
+  // center again, which shares its cache key in this stub).
+  assert.deepEqual(service.calls, { reverse: 2, nearby: 1 });
+  assert.ok(labels.placeLabels.length > 0);
+});
+
+test('a small pan reuses the last lookup; a real move looks up again', async () => {
+  const { viewer, state } = createViewer({
+    latitude: 30.26,
+    longitude: -97.74,
+    heightM: 600,
+  });
+  const service = createService();
+  const first = await getBasemapLabelContext(viewer, service);
+  assert.deepEqual(service.calls, { reverse: 1, nearby: 1 });
+
+  state.latitude += 0.0005; // ~55 m at 600 m height
+  const panned = await getBasemapLabelContext(viewer, service, {
+    previous: first,
+  });
+  assert.deepEqual(
+    panned.placeLabels,
+    first.placeLabels,
+    'the same area keeps its labels',
+  );
+  assert.deepEqual(service.calls, { reverse: 1, nearby: 1 });
+
+  state.latitude += 0.002; // ~280 m from the first lookup
+  const moved = await getBasemapLabelContext(viewer, service, {
+    previous: panned,
+  });
+  assert.notDeepEqual(moved.placeLabels, first.placeLabels);
+  assert.deepEqual(service.calls, { reverse: 2, nearby: 2 });
+});
+
+test('over high terrain the visible width is measured from the ground', async () => {
+  // 100 m above a 3000 m plateau shows ~115 m across, not the ~3.6 km a
+  // 3100 m ellipsoid height would suggest.
+  const { viewer, state } = createViewer({
+    latitude: 30.26,
+    longitude: -97.74,
+    heightM: 3100,
+    groundM: 3000,
+  });
+  const service = createService();
+  const first = await getBasemapLabelContext(viewer, service);
+  state.latitude += 0.0045; // ~500 m
+  await getBasemapLabelContext(viewer, service, { previous: first });
+  assert.equal(service.calls.reverse, 2);
+});
+
+test('crossing into the Nearby Places height looks up again', async () => {
+  const { viewer, state } = createViewer({
+    latitude: 30.26,
+    longitude: -97.74,
+    heightM: 30_000,
+  });
+  const service = createService();
+  const high = await getBasemapLabelContext(viewer, service);
+  assert.equal(service.calls.nearby, 0);
+  state.heightM = 20_000; // a 1.5× zoom, under the distance rule
+  const low = await getBasemapLabelContext(viewer, service, { previous: high });
+  assert.equal(service.calls.nearby, 1);
+  assert.ok(low.nearbyPlaceLabels.length > 0);
+});
+
+test('a lookup that timed out is completed from the cache, not frozen', async () => {
+  const { viewer, state } = createViewer({
+    latitude: 30.26,
+    longitude: -97.74,
+    heightM: 600,
+  });
+  const service = createService();
+  let answer;
+  service.reverseGeocode = () => {
+    service.calls.reverse += 1;
+    return new Promise((resolve) => {
+      answer = resolve;
+    });
+  };
+  // Expire the 1.5 s wait at once.
+  const { setTimeout: wait } = globalThis.window;
+  globalThis.window.setTimeout = (fn) => wait(fn, 0);
+  let first;
+  try {
+    first = await getBasemapLabelContext(viewer, service);
+  } finally {
+    globalThis.window.setTimeout = wait;
+  }
+  assert.deepEqual(first.placeLabels, []);
+  assert.ok(
+    first.nearbyPlaceLabels.length > 0,
+    'the nearby answer arrived in time',
+  );
+
+  answer({ formattedAddress: 'Late place', labels: [] });
+  await new Promise((resolve) => setImmediate(resolve));
+  state.latitude += 0.0005;
+  const next = await getBasemapLabelContext(viewer, service, {
+    previous: first,
+  });
+  assert.deepEqual(next.placeLabels, ['Late place']);
+  assert.deepEqual(
+    service.calls,
+    { reverse: 1, nearby: 1 },
+    'the late answer is a cache hit',
+  );
+});
+
+test('an empty answer is asked again rather than held', async () => {
+  const { viewer, state } = createViewer({
+    latitude: 30.26,
+    longitude: -97.74,
+    heightM: 600,
+  });
+  const service = createService();
+  service.reverseGeocode = async () => {
+    service.calls.reverse += 1;
+    return null;
+  };
+  const empty = await getBasemapLabelContext(viewer, service);
+  state.latitude += 0.0005;
+  await getBasemapLabelContext(viewer, service, { previous: empty });
+  assert.deepEqual(
+    service.calls,
+    { reverse: 2, nearby: 1 },
+    'the cached nearby answer is not asked again',
+  );
+});
+
+test('a failed lookup is asked again once the provider recovers', async () => {
+  const { viewer, state } = createViewer({
+    latitude: 30.26,
+    longitude: -97.74,
+    heightM: 600,
+  });
+  const service = createService();
+  const working = service.reverseGeocode;
+  service.reverseGeocode = async () => {
+    service.calls.reverse += 1;
+    throw new Error('503');
+  };
+  const failed = await getBasemapLabelContext(viewer, service);
+  assert.deepEqual(failed.placeLabels, []);
+
+  service.reverseGeocode = working;
+  state.latitude += 0.0005;
+  const recovered = await getBasemapLabelContext(viewer, service, {
+    previous: failed,
+  });
+  assert.ok(recovered.placeLabels.length > 0);
+  assert.deepEqual(
+    service.calls,
+    { reverse: 2, nearby: 1 },
+    'only the failed geocode is asked again',
+  );
+});
+
+test('cached-only lookups read every cached viewport sample and never request', async () => {
+  const { viewer, state, degreesPerPixel } = createViewer({
+    latitude: 30.26,
+    longitude: -97.74,
+    heightM: 20_000,
+  });
+  const service = createService();
+  // Geocode view A's upper-left sample (screen x = 300).
+  const a = await getBasemapLabelContext(viewer, service);
+  const cachedLabel = a.placeLabels.find(
+    (label) => label.startsWith('Area') && label !== 'Area 30.2600,-97.7400',
+  );
+  assert.ok(cachedLabel, 'the upper-left sample was geocoded');
+  // View B puts that same point at its upper-right sample (screen x = 900),
+  // which only a read of every sample finds.
+  state.longitude -= 600 * degreesPerPixel();
+  const before = { ...service.calls };
+  const b = await getBasemapLabelContext(viewer, service, { cachedOnly: true });
+  assert.ok(b.placeLabels.includes(cachedLabel));
+  assert.deepEqual(service.calls, before);
+});